A recent Wisconsin based study has just concluded after a 20 year longitudinal analysis was done over an adult cohort of 4,926 participants. The researchers were evaluating the association of regular aspirin use with incidence of age-related macular degeneration (AMD). It was found that aspirin may cause macular degeneration.
Macular degeneration is a process usually affecting older adults in which their macula, part of the retina that is the center of visual field and area responsible for sharpest day as well as color vision, is deprived of blood and degenerates. This can happen because either debris got in the area between retina and choroid, blood supply layer of the eye, or excess blood vessels grew in and detached the retina. It was hypothesized that long-term, regular aspirin use may contribute to the development of the later form of AMD.
Eye examinations were performed every five years for participants age 43-86. Patients were asked if they used aspirin regularly, defined as at least twice every week over three months. Aspirin use over a 10 year period was associated with late AMD, but not early. However, aspirin use over a 5 year period was not significantly associated with either type of AMD. A 14.8 year (average) followup showed 512 late AMD 117 early AMD cases. Specifically,
– 10 year use was associated with greater late AMD
— Hazard ratio (HR): 1.63, Confidence interval (CI): 95% from 1.01 to 2.63, P=0.05
— Regular user incidence of AMD: 1.76%, CI: 95% from 1.17% to 2.646%
— Non-user incidence of AMD: 1.03%, CI: 95% from 0.70% to 1.51%
– 10 year use was associated with greater late neovascular AMD
— HR: 2.20, CI: 95% from 1.20 to 4.15, P=0.01
Since nearly 20% of adults in the U.S. use aspirin regularly, these findings were significant for aspirin users and the ophthalmologists treating them. If the mechanisms behind this link are discovered, it can very well help treat or prevent vision loss due to late neovascular AMD and related conditions.
Barbara E. K. Klein, Kerri P. Howard, Ronald E. Gangnon, Jennifer O. Dreyer, Kristine E. Lee, Ronald Klein. 2012. Long-term Use of Aspirin and Age-Related Macular Degeneration. The Journal of the American Medical Association.